W. Bradford Wilcox, director of UVA’s Project, chaired the team of family-scholar experts — including William Galston and Ron Haskins of Brookings, as well as David Popenoe of Rutgers and Judith Wallerstein of Berkeley — who put the study together. In an interview with National Review Online, Wilcox talks about the findings and how they can be put to practical use.

KATHRYN JEAN LOPEZ: If there is one thing people should pay attention to from this study, what should it be?

W. BRADFORD WILCOX: That couples should get married before having children or bringing a new romantic partner into the home. This is because cohabitation and children do not mix well, according to the research on children.

LOPEZ: So, American kids growing up today are more likely to see their parents cohabit, not divorce? That has got to be good news, right?

WILCOX: Alas, no.

But, first, there is good news in the report. The good news is that couples who marry before having children are less likely to divorce than couples who got married in the 1970s and 1980s — the height of the divorce revolution. Divorces involving children have almost returned to their early-1960s levels, before the divorce revolution hit America. So only about 24 percent of American children born to married parents will see their parents divorce before they turn 12.

But the bad news is that more than 40 percent of American children will experience a parental cohabitation by age 12. So, even as divorce falls, cohabitation rises in the lives of American children. This is bad news because children in cohabiting relationships are more likely to do poorly in school, to use drugs, to have emotional problems, and to be abused, compared with children in intact, married families. Cohabiting relationships are also much less stable than marriages, and kids don’t do well when they are exposed to serious instability — parents and partners exiting and entering the home.

LOPEZ: But isn’t cohabitation at least better than divorce?

WILCOX: Not from the child’s perspective. This was the most surprising thing to me in reviewing the growing research on cohabitation and children. When it comes to outcomes like educationanddrug use, kids in cohabiting homes do about as poorly as kids from divorced homes.

And when it comes to abuse, children in cohabiting homes are much more likely to be abused, compared to kids in stable single-parent homes. In fact, children living with their mother and an unrelated male boyfriend are more than twice as likely to be physically, sexually, or emotionally abused, compared with children living with a single mother who doesn’t bring an unrelated adult into the home.

So cohabitation seems to pose about as much of a risk to children as does divorce.

LOPEZ: What’s most harmful about cohabitation?

WILCOX: I think the instability associated with cohabitation is probably the most harmful thing about it. One study mentioned in the report found that 24 percent of kids born to married parents saw their parents break up by age 12, compared with 65 percent of kids born to cohabiting parents.

And a lot of new research on kids is telling us that they thrive on routine, stability, and enduring relationships with their caretakers (once known as parents and grandparents). Because cohabitation is so unstable, it dramatically increases the odds that kids who find themselves in cohabiting households will be exposed to a relational carousel, where parents and partners are exiting or entering the home. This instability can be hard for kids to handle.

LOPEZ: But it’s so mainstream — not just as your numbers demonstrate, but throughout pop culture. It’s now considered a happy ending in a romantic comedy.

WILCOX: Yes, well life does not imitate art in this regard. Clearly many children do not experience a happy ending when mom and dad cohabit, or — worse yet — when mom and her boyfriend move in together.

LOPEZ: What is the state of divorce? Is it down only because people aren’t bothering to get married anyway?

WILCOX: That is part of the story. Today, the college-educated, the affluent, and the religious are more likely to marry than the less-educated, the poor, the working class, and the less-religious. So marriage is a more selective institution than it used to be.

Another reason divorce is down is that teenage marriage has almost disappeared. This is important because teen marriages are more likely to end in divorce.

But public attitudes toward divorce have also grown more negative. The whole myth of the happy divorce is increasingly rejected in society — especially among college-educated Americans. Even the New York Times ran a story on “How Divorce Lost Its Groove“ among college-educated Americans. So the cultural turn away from easy divorce has made marriage more solid.

LOPEZ: Does this come down to Americans having a commitment problem? A marriage-model problem?

WILCOX: Well, I think many Americans — especially working-class and poor Americans — are gun-shy when it comes to marriage. They are concerned that they don’t have the economic resources and the emotional resources to make a go at marriage. And, yes, the instability they have witnessed in their own families — and among their own friends — makes them commitment-phobic.

LOPEZ: For people who talk about the “haves and have-nots,” should marriage come up a lot more than it does? How much of this is an economic issue? A social-justice issue — to use a term of political art?

WILCOX: Yes, marriage should come up a lot more for Americans who are concerned about social justice, as I pointed out in a recent New York Times piece, “Marriage Haves and Have-Nots.”

One recent study found that the breakdown of marriage accounts for about 41 percent of the increase in family income inequality in this country from 1976 to 2000. Indeed, the nation’s ongoing retreat from marriage is hitting poor and working-class Americans hardest, as Andrew Cherlin and I pointed out in a recent policy brief for the Brookings Institution.

So this is one reason why progressives should care about the strength and stability of marriage in America.

But I should also say that my research indicates that the economic changes of the last 40 years have not served working-class and poor communities well. For instance, it’s much harder for American men with a high-school degree (but not a college degree) to find decent, stable work today than it was in the 1950s and the 1960s. This makes it harder for these men to get and stay married. So conservatives concerned about the family fabric of our society should also pay attention to strengthening the economic foundations of family life in poor, working-class, and even middle-class communities.

LOPEZ: Why do we as Americans have an interest in encouraging marriage?

WILCOX: One reason is that marriage has been a stabilizing force and an engine of economic opportunity in many working-class and middle-class communities throughout our nation’s history. And yet marriage is now in retreat in many of these communities, where high-school-educated adults predominate. This is troubling, because as Andrew Cherlin and I say in our Brookings Policy Brief, “The institution of marriage has been an important pillar of the American Dream, and the erosion of marriage in Middle America is one reason the dream is increasingly out of reach for men, women, and children from moderately-educated homes.”

LOPEZ: “Married men earn more money than do single men with similar education and job histories.” Is that conclusion meant to be a nudge to the failure-to-launch-ers?

WILCOX: Marriage isn’t just good for kids on average. It’s also good for adults. In the case of men, we know from the work of economist Robert Lerman that men in the U.S. who get and stay married work harder, work longer hours, and earn about 20 percent more than their unmarried peers.

So, if you’re a guy, marriage may be a real boon to your work effort and success.

LOPEZ: Can a teacher starting the school year easily predict that the kids in divorced or cohabiting parents won’t do as well as a general rule?

WILCOX: Yes. Now, it’s important to acknowledge here that most kids from cohabiting and divorced homes do fine in school. Nevertheless, they are about twice as likely to have problems in school and to drop out of high school, compared with children in intact, married families.

So cohabitation and divorce put kids at greater risk of failing in school, even if most kids in these families do not fail. And classes that have large numbers of children from unmarried or single homes are more likely to be challenging for teachers.

LOPEZ: How did this whole marriage study begin and how has it changed over the years?

WILCOX: This report began about a decade ago as an effort by the Institute for American Values to understand what the research tells us about the ways in which marriage matters for children, adults, and communities. In the first two editions, the primary focus was on single parenthood and divorce. But the third edition focuses much more on cohabitation.

This is because the evidence suggests the following: Today in America, cohabitation now poses a greater risk to children than does divorce.